When finding the molecular formula of a compound the total weight of the compound is necessary assumptions as in the case for the empirical formula are not valid here. If you have 2000 mL of a 300 aqueous solution. However neither formula indicates the arrangement of atoms in a molecule.
Based on the assumption that there are 100 grams of the unknown substance you can determine that the number of grams present for each element equals the percentage value.
The molecular formula lists the numbers of each type of element and can be used in writing and balancing chemical equations. Based on the assumption that there are 100 grams of the unknown substance you can determine that the number of grams present for each element equals the percentage value. In chemistry the empirical formula of a chemical compound is the simplest positive integer ratio of atoms present in a compound. For example the molecular formula of glucose is C 6 H 12 O 6 but the empirical formula is CH 2 O.